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Chapter 9: Database Management Approaches
1. A distributed database is a single logical database that is physically divided among computers at several sites
on a network.
2. Accessing data using messages over a network is substantially slower than accessing data on a disk.
3. Seek delay refers to the fixed amount of time that is required for every message.
4. In a DDBMS, the site where the user is located is called the remote site.
5. A characteristic of a DDBMS that states that users do not need to be aware of the location of the data in a
database is known as replication transparency.
6. If users are unaware of fragmentation, the DDBMS has fragmentation transparency.
7. A local deadlock involves one transaction that requires a record held by a second transaction at one site, while
Chapter 9: Database Management Approaches
the second transaction requires a record held by the first transaction at a different site.
8. A global deadlock occurs at a single site in a distributed database.
9. A file server stores the files required by the users on a network.
10. On a client/server network, the server is a computer that provides data to the clients.
11. The server is also known as a front-end processor or front-end machine.
12. If the client only performs the presentation functions (and not the business functions), then the client is known as a fat
client.
13. Each Web page is assigned an Internet address called a Uniform Resource Locator (URL).
Chapter 9: Database Management Approaches
14. An XML document should begin with an XML declaration.
15. Access to a data warehouse is accomplished through the use of OLAP software.
16. In order to view and analyze higher levels of aggregate data, you must drill down the data.
17. When relational databases store complex objects, these special data types are known as VLOBs.
18. The term class refers to the general structure of an object.
19. The actions defined for a class are known as methods.
20. One approach you can use to model all the various aspects of software development for object-oriented systems is
known as UML.
21. When computers at one site need to be connected with computers at another site, the connection must be within a
____.
22. Computers in a network communicate through ____.
23. The formula for message transmission time is: communication time = access delay + (data volume / X), where X
represents ____.
24. A DDBMS that has at least two sites at which the local DBMS are different is known as a ____.
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25. When users are unaware of the steps taken by the DDBMS to update the various copies of data, this characteristic of
the DDBMS is called ____.
fragmentation transparency
26. Which of the following is an advantage of distributed databases?
Easier updates of replicated data
More complex query processing
More complex treatment of concurrent updates
27. When a centralized database becomes unavailable for any reason, no users can continue processing. In contrast, if a
local database in a distributed database becomes unavailable, only users who need that data are affected. Because of this,
distributed databases have a(n) ____ advantage over a centralized database.
increasing database capacity
28. It is possible for local DBMSs to commit updates at some sites and undo updates at other sites. This inconsistency can
be prevented by using a ____.
29. The site that initiates the update in a two-phase commit is known as the ____.
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Chapter 9: Database Management Approaches
30. ____ implies that the performance of functions such as adding sites, changing versions of DBMSs, creating backups,
and modifying hardware should not require planned shutdowns of the entire distributed database.
Fragmentation transparency
31. ____ implies that users should not need to be concerned with the location of any specific data in the database.
Fragmentation transparency
Distributed query processing
32. ____ implies that no site should depend on another site to perform its database functions.
No reliance on a central site
Fragmentation transparency
33. ____ is the ability of a computer system to continue to function well as utilization of the system increases.
34. Because the clients and the server perform different functions and can run two different operating systems, there is an
arrangement of client/server architecture known as ____.
Chapter 9: Database Management Approaches
35. If the client, in a client/server system, performs the business functions (calculations, etc.), then this client is known as
a(n) ____.
36. Each digital document on the Web is called a ____.
37. ____ is the data communication method used by Web clients and Web servers to exchange data on the Internet.
38. ____ is a metalanguage derived from a restricted subset of SGML, and designed for the exchange of data on the Web.
Chapter 9: Database Management Approaches
39. When users interact with an RDBMS, they use transactions. These types of systems are called ____ systems.
40. When the data is organized by entity rather than by the application that uses the data, it is called ____.
41. With respect to the definition of data warehouse, ____ means that data is stored in one place, even though it originates
from everywhere in the organization and from a variety of external sources.
42. With respect to the definition of data warehouse, ____ means that the data is read-only.
43. With respect to the definition of data warehouse, ____ means that data in a data warehouse represents snapshots of
data at various points in time in the past.
Chapter 9: Database Management Approaches
44. A ____ is a subject-oriented, integrated, time-variant, nonvolatile collection of data in support of management’s
decision-making process.
45. Each ____ contains a single-part primary key that serves as an index for the fact table and also contains other fields
associated with the primary key value.
46. A(n) ____ consists of rows that contain consolidated and summarized data.
47. Uncovering new knowledge, patterns, trends, and rules from the data stored in a data warehouse is known as ____.
fragmentation transparency
48. In ____ systems, data and actions are encapsulated.
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Chapter 9: Database Management Approaches
49. In ____ systems, you create actions as part of data manipulation rather than as part of data definition.
50. ____ refers to the association of an operation to actual program code.
51. A(n) _________________________ is a DBMS capable of supporting and manipulating distributed
databases.
52. A(n) ____________________ DDBMS is a database that has the same local DBMS at each site.
53. ____________________ link one Web page to another or link to another location in the same Web page.
54. Web pages that display the same content for all Web clients are called ____________________ Web pages.
Chapter 9: Database Management Approaches
55. E-commerce between organizations is called ____________________.
56. ____________________ implies that you define an object to contain both the data and its associated actions.
57. A(n) ______________________________ is one in which data and the actions that operate on the data are
encapsulated into objects.
58. A(n) ____________________ is the set of values that are permitted for an attribute.
59. Methods are defined during the ___________________ process.
60. To execute the steps in a method, the user sends a(n) ____________________ to the object.
61. With respect to UML, the type of diagram most relevant to database design is the ____________________.
62. On a class diagram, the lines joining the classes represent the relationships and are called ____________________.
63. On a class diagram, a(n) ____________________ symbol precedes each attribute.
64. The ____________________ symbol in a class diagram indicates whether other classes can view or update
the value in the attribute.
65. With ____________________ visibility, any other class can view or update the value of an attribute.
66. With ____________________ visibility, only the class itself or public or protected subclasses of the class
can view or update the value in the attribute.
67. With ____________________ visibility, only the class itself can view or update the value in the attribute.
68. ____________________ indicates the number of objects that can be related to an individual object at the
other end of the relationship.
69. ____________________ are restrictions placed on the data that can be stored in the database.
70. If one class is a subclass of a second class, the second class is called a(n) ____________________ of the
first class.
Chapter 9: Database Management Approaches
71. What are the advantages of distributed databases?
72. What are the advantages of a client/server system?
73. Explain the difference between a Web page, a Web server, and a Web client.
74. Discuss the differences between how client-side extensions and server-side extensions are created and executed,
including the kinds of languages used to create them.
75. What is the purpose of the following UML diagrams: class, use case, sequence, and activity?